Ive had my Playstation 3 for about 2 years and I have never had a problem like this before. I can play for about 30-35 minutes then the game freezes. I can look around depending on the game, and can press the PS button to do things on the menu. If I choose to quit game it will go to the Please Wait screen and then beep three times and totally freeze into a black screen. If I reboot the Playstation then it will not see the disc and I cannot play at all. I have to wait and then reboot. If i turn it on too soon It will not see the disc. I think it's an overheating problem but it's never happened before until recently. There are no red or yellow lights flashing its all green and blue. Any ideas?